Going to the health club might seem the simplest of acts: You show up, do your workout whether it's lifting weights, taking a class or playing a game of racquetball and then you're done.

But avid gym-goers can be setting themselves up for injury, says Kevin Plancher, MD, a leading sports orthopaedist in the New York metropolitan area. And wrist and ankle injuries both the sudden and the chronic kind can be especially problematic. Ankles are essential for all normal activity, from walking down the street to running a marathon, and repeated (or untreated) injuries can permanently damage them. For its part, the wrist is one of the most complex joints in the body, with 15 bones and an elaborate system of ligaments holding it all together. "That means that when something goes wrong in the wrist, it can be tough to fix and its critical to see an orthopaedic hand surgeon specialist."

Here are six ways to keep your wrists and ankles safe at the gym:

Choose the right shoes. "If you participate in an activity more than three times a week, you should be wearing shoes specifically designed for that activity," Plancher says. This can do a lot to protect your ankles, he says. Ankle sprains, the most common sports-related injuries, occur when a ligament in the ankle is strained beyond its normal limits. Sprains can strike when your ankle "rolls" to the side, wrenching the ligaments (and leaving you sidelined for several weeks). "Lots of people wear running shoes to the gym, but running shoes are designed for just that," explains Plancher. "They put your foot and leg into the best position to propel you forward." That means wearing running shoes when you're playing a sport that incorporates lots of side-to- side movements, like tennis, basketball or squash, could leave you with a sprained or even broken ankle. Shoes designed for cross-training would be more appropriate in these situations.

Reduce overuse. Believe it or not, carpal tunnel syndrome is not just for desk jockeys. "Anyone who subjects his or her hands and wrists to repetitive movements can get carpal tunnel syndrome," Plancher says. "It's fairly common among people who play racquet sports, as well as people who regularly work out on rowing machines and stationary bikes." The first sign is often a burning or tingling feeling or the sensation that your hands or fingers are "falling asleep." Over time, carpal tunnel syndrome can result in permanent nerve damage. Ankles are subject to their own type of repetitive stress injury: Tarsal tunnel syndrome, which is generally caused by ill-fitting shoes that irritate and inflame the ligaments running from the foot to the ankle.

Watch your form. If you like to lift, be sure you're doing it perfectly, says Plancher. "Weightlifters experience high compression forces on their wrists, and that force can cause sprains and other injuries." Likewise, tennis (and other racquet sports) players should pay attention to their form to avoid the type of rapid or awkward rotation that can disrupt the stability of the wrist. "Throwing or twisting your arm in an unnatural way, especially if you do it in a rapid, explosive way, can seriously injure the ligaments in your wrist," Plancher says.

If the bike fits: Cyclists (including spinning class aficionados) are prone to a condition called "handlebar" or cyclist's palsy. When you lean your hands on the handlebars and bend your wrists backwards, the pressure can compress the ulnar nerve, which runs through the palm and up into the wrist. Like carpal tunnel syndrome, cyclist's palsy can be a serious condition, resulting in permanent nerve damage if not treated properly. The answer: Make sure that your bike is fitted properly. (This can be tricky if you use a different bike every time you hit the gym, so be sure to give yourself a few minutes to adjust the saddle and handlebars before you start pedaling.) "Riding on a bike that doesn't fit can make you lean too far forward and put extra strain on your hands and wrists," Plancher says. Invest in padded cycling gloves, switch hand positions during your ride, and periodically shake out your hands and stretch your forearms.

Stretch and strengthen. To protect your wrists, take the time to stretch the muscles in your forearms and hands before working out, and take frequent "stretching breaks" during your workout, Plancher advises. Ankles will benefit from stretching your lower legs: Achilles tendon and calves as well as shins. To help keep ankles stable (and sprain-free), strengthen the muscles in your lower legs with exercises like calf raises. Likewise, keep your wrists healthy by building strength in your forearms, upper arms (triceps and biceps) and shoulders. "Doing appropriate strengthening exercises builds strength, but it also increases your mobility and range of motion, both of which help you avoid injury," Plancher says.

Don't tough it out. "Many athletes feel they should 'work through the pain,'" Plancher says, "and that might be good advice if your 'pain' is plain old muscle fatigue. Maybe you're starting a new routine or you're simply feeling tired or uninspired in your regular workout. But it's absolutely the worst thing you can do with a joint injury." Continuing an activity that's caused or exacerbated an injury to your ankles or wrists can cause serious, even permanent damage. A better rule, says Plancher: "Don't do any activity that hurts, and don't return to an activity until you're pain-free."

Kevin D. Plancher, MD, MS, FACS, FAAOS, is a leading orthopaedic surgeon and sports medicine expert with treatment in knee, shoulder, elbow and hand injuries. Dr. Plancher is an Associate Clinical Professor in Orthopaedics at Albert Einstein College of Medicine in NY. He is on the Editorial Review Board of the Journal of American Academy of Orthopaedic Surgeons.In 2001, he founded "The Orthopaedic Foundation for Active Lifestyles", a non- profit foundation focused on maintaining and enhancing the physical well-being of active individuals through the development and promotion of research and supporting technologies. For more info, visit www.plancherortho.com or www.ofals.org.